Extraction of zinc from zinc blende is achieved by:

Options

A. electrolytic reduction
B. roasting followed by reduction with carbon
C. roasting followed by reduction with another metal
D. roasting followed by self-reduction

Answer

To extract zinc from zinc blende (zinc sulfide, ZnS), we follow a two-step process: roasting and reduction. Here’s a step-by-step breakdown of the extraction process:

### Step 1: Roasting of Zinc Blende
1. **Conversion of Zinc Blende to Zinc Oxide**:
- The first step involves roasting the zinc blende in the presence of oxygen. This process converts the zinc sulfide (ZnS) into zinc oxide (ZnO) and sulfur dioxide (SO₂).
- The balanced chemical equation for this reaction is:
\[ 2 \text{ZnS} + 3 \text{O}_2 \rightarrow 2 \text{ZnO} + 2 \text{SO}_2 \]

### Step 2: Reduction of Zinc Oxide
2. **Reduction of Zinc Oxide to Zinc**:
- In the second step, the zinc oxide obtained from the roasting process is reduced to metallic zinc using carbon (usually in the form of coke).
- The balanced chemical equation for this reduction reaction is:
\[ \text{ZnO} + \text{C} \rightarrow \text{Zn} + \text{CO} \]
- This reaction occurs at high temperatures, typically above 1270 K.

### Conclusion
- Therefore, the overall process for extracting zinc from zinc blende involves roasting followed by reduction with carbon.

### Final Answer
Zinc is extracted from zinc blende by roasting followed by reduction with carbon.

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